The invention relates to a transmission with a power take-off drive unit.
Transmissions with power take-off drives are used in utility vehicles, where the drive motor not only serves for driving the vehicle, but also for driving additional assemblies. These additional assemblies can be assemblies used during the drive operation, but also assemblies which are used independently of the drive operation. In the area of utility vehicles there are for example building material transport vehicles, where the drive motor is also used to drive a building material pump, for example a concrete pump. Drilling devices of prospecting vehicles or hydraulic assemblies and generators may also be driven as additional assemblies by the drive motor of a utility vehicle.
Transmissions with power take-off conventionally provide the desired performance via a power take-off transmission with an auxiliary drive shaft which is a part of the power take-off transmission.
A transmission with a power take-off as produced by the assignee of this application, on which the present invention is based, has, in addition to an input shaft to which the flywheel of a drive motor is connected, an intermediate shaft, a shift transmission shaft, a power take-off transmission shaft, a transmission input clutch, an intermediate clutch and a power take-off transmission clutch. Via this transmission, the intermediate shaft is connected to the input shaft via a transmission input clutch, wherein this transmission input clutch is also the drive clutch. Further, in this transmission, the shift transmission shaft is connected to the intermediate shaft via an intermediate clutch.
To facilitate connecting the power take-off transmission shaft, the power take-off transmission clutch is a synchronizing clutch, in particular, a multi-disk clutch, whereby the power take-off transmission engages a shaft which is permanently drive-connected to the input shaft. Especially if the full power of the drive motor is to be taken up by the power take-off drive shaft, high demands are made of the power take-off transmission clutch, so that a transmission with such a power take-off drive is quite expensive.
DE 1287941 discloses a variable speed transmission of a range-change transmission type with a power take-off drive for agricultural tractors, in which the power take-off drive is driven by an output shaft of the variable speed transmission. The variable speed transmission can not be disconnected during stand-still periods of the tractor to permit operation of the auxiliary drive independently of the drive operation of tractor in order to make a transmission input clutch of the variable speed transmission available for operation with the auxiliary power take-off drive.
It is the object of the present invention to reduce the expenditures for the manufacture of a transmission with a power take-off drive.